Die Rolle von Phytohormonen bei der Interaktion zwischen phytopathogenen Pilzen und ihren Wirtspflanzen

• Applicant: Professor Dr. Paul Tudzynski
• Subject Area: Organismic Interactions, Chemical Ecology and Microbiomes of Plant Systems
• Term: from 1997 to 2006
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5393236

Interactions of microorganisms and higher plants often are accompanied by changes in phytohormone levels. The specific contributions of both partners to these changes and their impact for the interaction are not yet resolved. Here the role of phytohormone balance in pathogenic associations will be studied focusing on Botrytis cinerea, the casual agent of grey mould of several important crop plants, and tomato as its host plant. A comprehensive approach will be taken integrating experiments at the whole plant level with molecular and biochemical studies at the cellular level. The influence of external application of phytohormones on the susceptibility of plants to infection by B. cinerea will be investigated in more detail (including inhibitors of phytohormone action or biosyntheses and mixtures). The input and importance of phytohormones produced by B. cinerea in planta will be analysed by combined biochemical and molecular methods. Hormone-biosynthetic gene will be cloned and characterized, focusing on abscisic acid, gibberellins, and ethylene. The availability of biosynthesis genes from B. Cinerea opens the possibility to analyse the expression of the fungal pathways in planta. Transgenic non- and overproducing strains will allow fuctional analyses of the role of specific fungal phytohormones for the interaction. The B. cinerea system will be compared with the related white mould fungus Sclerotinia sclerotiorum and the biotrophic powdery mildew fungus Sphaerotheca fusca syn. fuliginea in order to gain a broader view of the general role of phytohormones. Defined plant mutants with blocked hormone biosynthesis and/or altered susceptibility to plant hormones will bei included in these studies.

• DFG Programme: Research Grants
• International Connection: Israel, Palestine
• Participating Persons: Professor Dr. Radwan Barakat, Ph.D.; Dr. Yigal Elad, Ph.D.; Privatdozent Dr. Amir Sharon